Sorgelig wrote:It's possible, but it will require every core modification specific to each core.
I'm not going to another round of 50 cores modification.
This is understandable. Most people play with the default dip switch settings anyway, as these are the only settings accepted for high score competitions. Maybe you can update just some of the more popular cores when you have some spare time. But this feature is definately not top priority.
Talking about Arcade cores: Have you considered to further improve the NES core so that (partial) support for the Nintendo VS Unisystem is added?
A first and easy step (as you already have a palette selection option) would be to add the Arcade palettes of the different VS PPUs.
They can be downloaded from here:
http://atariage.com/forums/topic/242970 ... try3884369
Here is a test rom that might help with the development:
https://forums.nesdev.com/viewtopic.php ... 92#p127592